Sat, 05 Jul 2008 00:21:08 BST CiteULike: dchen Makse http://www.citeulike.org/user/dchen/author/Makse CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/dchen/article/2731428 <i>Nature, Vol. 415, No. 6872. (7 February 2002), pp. 614-617.</i> Testing the thermodynamic approach to granular matter with a numerical model of a decisive experiment Hernan Makse Jorge Kurchan doi:10.1038/415614a Nature, Vol. 415, No. 6872. (7 February 2002), pp. 614-617. 2008-04-29T00:49:56-00:00 2002 Nature 415 6872 614 617 grains makse nature simulation http://www.citeulike.org/user/dchen/article/2731415 <i>Proceedings of the National Academy of Sciences, Vol. 102, No. 7. (15 February 2005), pp. 2299-2304.</i><br /><br />A densely packed granular system is an example of an out-of-equilibrium system in the jammed state. It has been a longstanding problem to determine whether this class of systems can be described by concepts arising from equilibrium statistical mechanics, such as an effective temperature and compactivity. The measurement of the effective temperature is realized in the laboratory by slowly shearing a closely packed ensemble of spherical beads confined by an external pressure in a Couette geometry. All of the probe particles considered in this study, independent of their characteristic features, equilibrate at the same temperature, given by the packing density of the system. 10.1073/pnas.0409911102 Experimental measurement of an effective temperature for jammed granular materials Chaoming Song Ping Wang Hernan Makse doi:10.1073/pnas.0409911102 Proceedings of the National Academy of Sciences, Vol. 102, No. 7. (15 February 2005), pp. 2299-2304. 2008-04-29T00:38:58-00:00 2005 Proceedings of the National Academy of Sciences 102 7 2299 2304 grains jamming makse temperature http://www.citeulike.org/user/dchen/article/2722865 <i>Physica A: Statistical Mechanics and its Applications, Vol. 327, No. 3-4. (15 September 2003), pp. 201-212.</i><br /><br />The micromechanics of a variety of systems experiencing a structural arrest due to their high density could be unified by a thermodynamic framework governing their approach to [`]jammed' configurations. The mechanism of supporting an applied stress through the microstructure of these highly packed materials is important in inferring the features responsible for the inhomo- geneous stress transmission and testing the universality for all jammed matter. In this paper, we present a novel method for measuring the force distribution within the bulk of a compressed emulsion system using confocal microscopy and explain our results with a simple theoretical model and computer simulations. We obtain an exponential distribution at large forces and a small peak at small forces, in agreement with previous experimental and simulation data for other particulate systems. Measuring the distribution of interdroplet forces in a compressed emulsion system Jasna Brujic Edwards Ian Hopkinson Hernán Makse doi:10.1016/S0378-4371(03)00477-1 Physica A: Statistical Mechanics and its Applications, Vol. 327, No. 3-4. (15 September 2003), pp. 201-212. 2008-04-27T00:12:13-00:00 2003 Physica A: Statistical Mechanics and its Applications 327 3-4 201 212 emulsion force technique http://www.citeulike.org/user/dchen/article/2280866 <i>Physical Review Letters, Vol. 84, No. 18. (1 May 2000), 4160.</i><br /><br />3D computer simulations and experiments are employed to study random packings of compressible spherical grains under external confining stress. In the rigid ball limit; we find a continuous transition in which the stress vanishes as (φ-φ c ) β ; where φ is the (solid phase) volume density. The value of φ c depends on whether the grains interact via only normal forces (giving rise to random close packings) or by a combination of normal and friction generated transverse forces (producing random loose packings). In both cases; near the transition; the system's response is controlled by localized force chains. Packing of Compressible Granular Materials Hernán Makse David Johnson Lawrence Schwartz doi:10.1103/PhysRevLett.84.4160 Physical Review Letters, Vol. 84, No. 18. (1 May 2000), 4160. 2008-01-23T15:02:23-00:00 2000 Physical Review Letters 84 18 4160 American Physical Society force grains packing qualifier